Hui-Fang Zhu

Syntheses and crystal structures of 1D tubular chains and 2D polycatenanes built from the asymmetric 1-(1-imidazolyl)-4-(imidazol-1-ylmethyl)benzene ligand with metal salts

Reactions of a new asymmetric ligand, 1-(1-imidazolyl)-4-(imidazol-1-ylmethyl)benzene (IIMB), with various metal [Cd(II), Mn(II), Zn(II)] salts led to the formation of molecular, one- (1D) and two-dimensional (2D) architectures [Cd(IIMB)2(H2O)(SO4)]·7.5H2O 1, [Cd(IIMB)2Cl2]·H2O 2, [Cd(IIMB)4(H2O)2](NO3)2·5H2O 3, [Cd(IIMB)(OAc)2]·H2O 4, [Mn(IIMB)2(SO4)(H2O)]·8.2H2O 5, [Mn(IIMB)4(H2O)2]Cl2·5H2O 6 and [Zn(IIMB)2]4(NO3)8·13.5H2O 7. All the structures were established by single-crystal X-ray diffraction analysis. Both compounds 1 and 5 with sulfate anion are 2D polycatenanes formed by the interlocking of 1D double-stranded chains, while 2 and 4 with chloride and acetate anions are 1D chains. The results provide nice examples of topologies of metal-organic frameworks controlled by the counter anions. Interestingly, 3 and 6 are discrete molecular complexes with monometallic cores and form 2D networks through strong intermolecular hydrogen bonds. Complex 7, obtained under the same conditions as 3, is a 1D tubular chain. The structural difference between 3 and 7 suggests the metal ions also have a significant effect on the construction of supramolecular architectures. Furthermore, the photoluminescence properties of these compounds were investigated in the solid state at room temperature.

Three-dimensional photoluminescent pillared metal-organic framework with 4.82 topological channels obtained from the assembly of cadmium(II) acetate and trimellitic salt

Reaction of the piperidinium salt of trimellitic acid (BTC3−) with cadmium(II) acetate dihydrate yields an unprecedented 3D pillared metal-organic framework, [Cd3(BTC)2(H2O)6]·3H2O, showing strong blue luminescence. The framework contains 4.82 topological channels, in which the ‘floors’ are directly connected by the pillars of the BTC3− benzene rings.

2D 4.82 Network with threefold parallel interpenetration from nanometer-sized tripodal ligand and lead(ii) nitrateElectronic supplementary information available: Fig. 1S. See http://www.rsc.org/suppdata/cc/b2/b207568g/

Reaction of nanometer-sized tripodal ligand 2,4,6-tris[4-(imidazol-1-ylmethyl)phenyl]-1,3,5-triazine (timpt) with lead(II) nitrate affords a novel polycatenated structure containing three interpenetrating 4.82 networks, in which the lead(II) atom has a hemidirected coordination geometry and a stereochemically active lone pair of electrons.

Self-assembly of a snake-like blue photoluminescent coordination polymer from 4,4'-bis(imidazol-1-ylmethyl)biphenyl and zinc acetate

A novel snake-like zinc(II) coordination polymer with blue photoluminescence, {[Zn(bimb)(OAc)2]·6H2O}∞ [bimb = 4,4′-bis(imidazol-1-ylmethyl)biphenyl, OAc = acetate anion], was obtained by reaction of Zn(OAc)2·2H2O with the ligand bimb. The X-ray crystal structural analysis indicates that two independent single-stranded helical chains are interwoven like two entwined snakes and held together through hydrogen bonds and π-π interactions.

Hydrothermal synthesis and structural characterization of one-dimensional coordination polymers of cobalt(II) and nickel(II) with 1,3,5-benzenetriacetic acid

Transition metal complexes [M(Hbta)(H 2 O) 4 ] [M=Co(II) ( 1 ), Ni(II) ( 2 ), H 3 bta=1,3,5-benzenetriacetic acid] have been prepared by reaction of H 3 bta with the M(OH) 2 in water by hydrothermal method. The complexes were characterized by X-ray crystallography and electrospray mass spectrometry. The coordination geometries around Co(II) and Ni(II) atoms are both distorted octahedral with O 6 donor set. And the conformation of flexible triacid is cis , trans , trans in the title complexes.

Synthesis and Crystal Structure of Blue Luminescent Cadmium(II) Coordination Networks with 4,4′-Bis(imidazol-1-ylmethyl)biphenyl from Different Solvent Systems

Two supramolecular complexes, [Cd(bimb)2Cl2] (1) and [Cd(bimb)(DMF)Cl2]·DMF (2) [bimb=4,4′-bis(imidazol-1-ylmethyl)biphenyl], were synthesized by reactions of CdCl2·2.5H2O with bimb ligand in ethanol and N,N′-dimethylformamide (DMF), respectively, and their structures were determined by X-ray crystallography. Complex 1 is an infinite 2D grid network bridged by bimb ligands, and the 2D sheets were further linked by C–H ⃛Cl hydrogen bonds to form a polycatenated 3D framework. Complex 2 has dicadmium(II) di-μ-chloride units which are connected by bimb bridging ligands to form an infinite non-interpenetrating 2D network. The results provide a nice example of the solvent system exerting a great effect on the construction of supramolecular frameworks.

Preparation, crystal structure and properties of novel Mn(III) complex with 1,3,5-benzenetriacetic acid

The reaction of benzene-1,3,5-triacetic acid (H3bta) with [Mn(salen)]ClO4·2H2O yields [Mn(salen)H2bta]·0.5H2O (1) [H2salen = N,N′-bis(salicylideneaminato)ethylene]. Complex 1 was characterized by X-ray crystal structure determination, elemental analysis, FT-IR and ES-MS spectroscopic methods. The X-ray crystallographic study reveals that the complex has a one-dimensional chain structure, and self-organizes to a three-dimensional network by O–H···O hydrogen bonds between the oxygen atom of carboxyl groups without deprotonation and the carbonyl oxygen atom of the bta ligand, and by C–H···O hydrogen bonds between the carbon atom of the salen group and the carboxyl oxygen atom of the bta ligand as well as the salen unit. In addition, 1 was studied by cyclic voltammetry.